The invention relates to a steering pole for a jet propulsion boat and more particularly to an improved control mast for such a watercraft.
A very popular type of watercraft is designed to be operated by a rider who either stands, heels or sits on a deck of watercraft and controls it by means of a mast that is pivotally supported at its lower end on the front of the watercraft so as to accommodate the rider's chosen operating position. This pivotal movement occurs about a generally transversely disposed pivot axis. Such a watercraft is shown in FIG. 1 and is identified generally by the reference numeral 11.
As may be seen, the watercraft 11 is comprised of a hull 12 having a rear deck portion 13 on which a rider, indicated at 14 may be positioned at any of the desired locations. This type of watercraft is normally powered by a small jet propulsion unit which is disposed beneath the rider's deck 13. This jet propulsion unit is driven by an internal combustion engine positioned forwardly of the rider's deck 13 and beneath a hatch 15. This jet propulsion unit has a pivotally supported steering nozzle which is steered by means of a steering control or handlebar 16 positioned at the upper end of a mast 17 which, in turn, pivotally supported at its lower end on the front portion of the hatch cover 15, in a manner which will be described.
FIG. 2 is a cross sectional view taken through a control-mast constructed in accordance with a type of prior art construction and wherein the control mast is indicated generally by the reference numeral 18. The control mast 18 is comprised of a core 19 that is formed from a foam plastic material and which has a recess 21 in which a tube 22 is contained. Wire actuators (not shown) pass through the tube 22 and are connected to the steering nozzle and throttle control for the engine for controlling the watercraft 11 in a well known manner.
In accordance with the prior art types of construction, the foam material 19 is contained within a two piece protective housing comprised of pieces 23 and 24 that are formed from a more rigid plastic material such as a fiberglass reinforced plastic which form a pivot for the handlebar assembly 16 at their upper end and the pivot to the hull at their lower end. Because of these structural requirements, the housing pieces 23 and 24 are quite heavy and large. In addition, the housing pieces 23 and 24 have overlapping portions, indicated at 25 which are secured to each other in a suitable manner such as bonding or the like. In order to provide good strength, these overlapping portions 25 must have sufficient length and hence the handle assembly 18 is of the prior art type and is quite heavy and tiring for the operator to hold. In addition, the center of gravity and moment of inertia is increased due to the heavy weight of the steering mast 18, particularly when the rider 14 is standing, and this gives rise to handling problems as well as making the boat somewhat unstable and more difficult to maneuver.
Also, because of the connections to the handlebar 16 and hull 12 for pivotal movement, the upper lower ends of the steering mast 18 are normally formed to be quite thick and heavy, aggravating the aforenoted problems.
It is, therefore, a principal object of this invention to provide an improved, light weight and easily manufactured control mast for a small watercraft.
It is further object of this invention to provide an improved lightweight control mast for a small watercraft that can be easily made and which will nevertheless have the necessary strength characteristics.